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4(No Model;-

H.v C. 'DOBS'ON 13mm. A No. 294,451'. Patented Mar. 4, 1884.

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1'0 au whom it may concern:

r UNITED STATES PATENT @Erica SPECIFICATION forming part of LettersPatent NTO. 294,451, dated March 4, 1884.

' Application filed January 18, ISES. (No model.)

Be it known that I, HENRY C. DoBsoN, a resident of the city, county, andState of New York, have invented certain Improvements in Banjos, Drums,and other Analogous Instruments, of which the following is aspeciiication.

This invention applies to all musical instruments which are constructedwith a parchment head stretched over a cylindrical rim or ring-such asbanjos, drums, and tambourines-and it relates to the construction ofthering or rim overwhich the head is stretched. These rings have beenheretofore made in variousways. In some instruments a flanged domeshapedring spun up from sheet metal has been placed on the top of thecylindrical ring, between it and the parchment, as shown in my PatentNo. 249,321, dated November 8, 1881. That patent illustrates what Ibelieve to be the most perfect and desirable construetion heretoforemade.

Figure l of the accompanying drawings is a v plan of the bottom or underside of a banjo.

constructed according to my present invention, onlya portion of thehandle being shown. Fig. 2 is a transverse section thereof cut in theplane of the line 2 2 in Fig. l, but drawn to a larger scale. Fig. 3 isan enlarged fragmentary section of the ring, showing its construction ofthree pieces. Fig. 4 is a similar view, showing a modified constructionof two pieces. Figs. 5 and 6 are fragmentary sections of the ring,showing modied shapes; and Fig. 7 is an elevation of a drum madeaccording to my present invention, one side thereof' being in section.

Referring to Figs. l and 2, let A designate lthe handle; B, the ring orrim; C, the parchment head stretched thereon; D, the straining-ring, andE E the clamps or tighteningscrews for drawing down the ring D andstraining the head. With the exception of the ring B, these parts are ormay be all constructed as shown in my said patent. The ring B, I nowmake of metal, and of tubular form in cross-section, as best seen inFig. 2. The metal tube (lettered c) is best formed of sheet-brass, andit is preferably re-enforced by a hoop of wood, b, arranged within it,as

shown; but this hoop should not fill all thc space within the tube, asit is desirable that the latter shall be at least partially hollow inorder to enhance the tone of the instrument by its bell-likereverberation. The wooden hoop b serves to stiffen the tubular ring, andpermits the use of thin sheet metal in the formation ofthe tube'a, bywhich the resonance of the latter is increased. At intervals around thering B holes or orifices c c are formed through the metal of the tube a,communicatingwith the hollowinterior of the ring. These holes facilitatethe escape of the sound-vibrations from the interior of the ring andaugment the volume of sound given out by the instrument, as well asimproving its tone. This hollow ring B, thus perforated, forms a sort ofsounding-box, the effect of which in amplifying and improving thetone ofmusical instrument-s is well known. The upper side of the tube a isswelled or dome-shaped in cross-section, being in shape similar to thecorresponding portion of the sheet-metal ring in my said patent, and forthe same purpose-namely, to afford 'a rounded corner, over which theparchment may be bent, and to provide a crowned elastic and resonantsupport for the parchment for somel distance inward from the peripheryof the instrument.

The tubular ring B may be made in many ways. It is possible to bend astraight metal tube, made in any of the known ways, into ring shape andjoin its ends by soldering or otherwise; but on account of the eXtremedifculty of this method I prefer to make the ring of two or more spunpieces of sheet metal, with seams extending around it, as shown inAFigs. 3 and 4. In Fig. 3 three pieces are employed, lettered d, e,andj'. The piece Z is a mere strip of sheet metal bent into hoop shapeand its ends joined together. The pieces c and f are spun up fromwasher-shaped blanks or rings of sheet metal to the shape shown, bothbeing alike, except where they lap. The three rings or pieces thus madeare lapped and soldered together, or they may be other- Wise fastenedtogether, either by lapping them or joining them edge to edge. In Fig. 4but two pieces are used, lettered g and h. Both are spun up fromcylindrical hoops similar to IGO sa j :2.94.4511

d. The hoop or piece li forms the inside of the ring I3, while g formsthe outside thereof, and they are seamed together at top and bottom.

The annular tube a, forming the ring B, may be of any one of variousshapes in cross-section. rIwo suitable shapes are shown in Figs. 5 and6.

The standards 'i fi for the tightening-screws E E may be fastened to thering B in several ways. In Fig. 2 they are shown as provided with screw-shanks which screw `into the wooden hoop b. In Fig. 5 they are shown asriveted to the outer portion or side of the tubular ring, in which ease,if the tube is made of thin metal, it should be lined with a ring oi'thicker metal, through which to rivet. In Fig. 6 the standard i has ascrew-shank7 which passes entirely through the tubular ring I3, and hasa nut, j, screwed on its end. To prevent the collapsing of the ring whentightening the nut, a washer, k, is placed in the hollow of the ringbefore inserting the shank,and the latter is passed through boththicknesses of the ring and the intervening` nut.

The handle A of the banjo is or may be attached to the ring B intheusual manner,and

the banjo is strung in the ordinary way.

Fig. 7 shows a drum the ring or cylinder of which is made according tomy present invention, but which is otherwise ol" the ordiA naryconstruction.

I am aware that a banjo has been patented the ring or rim of which ismade wholly oi' metal, with its top and bottom edges flanged or spunover internally for a short distance; but I am not aware that any banjohas eveiyet been made or patented the ring or rim of which consists ofan annular metal tube. I am also aware that banj os have been made witha wooden rim or ring mounted on legs above an annular woodensounding-box; but this is not the equivalent of my invention, as in mybanjo the rim and sounding-box are identical, the annular tube of,resonant metal serving the purposes of both. Another banjo has the usualwooden rim with a wire-like ring or slender metallic tube elevated onstandards slightly above the rim, with the parchment stretched over saidmetallic ring.

I claim as my invention- 1. A banjo or other parchment-head instrument,the main rim of which, composing the body of the instrument, is made ofan annular ni etallie tube forming a sounding-box7 substantially as setforth.

2. In a banjo or other parchment-head instrument, the combination of arim made of an annular metallic tube forming a soundingbox, a parchmenthead strained over said rim, a series ol' standards iixed to said rim, astraining-ring for stretching said head, and tightening devices engagingsaid standards 'for drawing down said ring, substantially as set forth.

3. A banjo or other parchment-head instrument7 the main rim ol" which7composing the body of the instrument, is tubular and made from sheetmetal, still'ened by a hoop ol' wood extending around it and within thehollow ol said tube, substantially as set i'orth.

et. A banjo or other parchment-head instrument, the ring or rim of whichconsists oi' an annular tube ot' sheet metal provided with apertures orsound-holes c c, affording communication between the annular hollow orcavity thereof and the external air, substantially as set forth.

5. A banjo or other parchment-head instrument, the ring or rim ot whichis formed ol' sheet metal in tubular form, the annular tube being builtup of two or more rings oi sheet metal with annular seams, substantiallyin the manner set forth.

6. The ring or rim of a banjo or other parchment-head instrument, builtup of three rings of sheet metal, two of which have outer and innerflanges and intermediate swelled or convex portions to form the top andbottom of the rim, while the third is of cylindrical shape to form theouter periphery ofthe rim, substantially as set forth.

In witness whereof I have hereunto signed my name in the presence of twosubscribing witnesses.

i-'rnivnr c. Dobson'.

lVit-nesses:

ARTHUR C. Faisan, HENRY CovNnrr`

